Re: [PATCH] fs/select: Annotate struct poll_list with __counted_by()

[Gustavo A. R. Silva]

On 08/08/24 09:00, Thorsten Blum wrote:

Add the __counted_by compiler attribute to the flexible array member
entries to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.

Signed-off-by: Thorsten Blum <thorsten.b...@toblux.com>

Reviewed-by: Gustavo A. R. Silva <gustavo...@kernel.org>

Thanks
--
Gustavo

---
  fs/select.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/select.c b/fs/select.c
index 9515c3fa1a03..1a4849e2afb9 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -840,7 +840,7 @@ SYSCALL_DEFINE1(old_select, struct sel_arg_struct __user *, 
arg)
  struct poll_list {
        struct poll_list *next;
        unsigned int len;
-       struct pollfd entries[];
+       struct pollfd entries[] __counted_by(len);
  };

#define POLLFD_PER_PAGE ((PAGE_SIZE-sizeof(struct poll_list)) / sizeof(struct pollfd))